JP2017215535A - Exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposure device that measures a feed amount of a substrate at a high accuracy to a long substrate and draws a pattern on both sides of the substrate in a state where flatness of the substrate is maintained.SOLUTION: An exposure device includes: first exposure means 23 including a light modulation element array; first substrate holding means 24 for holding a part of a longitudinal direction of a long substrate in a flat state; first relative movement means 25 for relatively moving the first exposure means 23 and the first substrate holding means 24 in the longitudinal direction of the long substrate; folding means 30 for folding a transportation path of the long substrate; second exposure means 43 including a light modulation element array; second substrate holding means 44 for holding a part in the longitudinal direction of the long substrate in a flat state; and second relatively moving means 45 for relatively moving the second exposure means 43 and the second substrate holding means 44 in the longitudinal direction of the long substrate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an exposure apparatus that draws a pattern on both sides of a long substrate while the long substrate is being fed from a supply reel and wound on a take-up reel.

  In general, as a base material of an electronic circuit board (printed circuit board) used for a mobile phone, a mobile device, etc., for example, a long board (photosensitive) having a thickness of 0.1 mm or less and a length of 500 mm or more (for example, 100 m). Long film) is used. In recent years, a direct exposure apparatus (maskless exposure apparatus) that draws a pattern by directly irradiating the substrate with drawing light without using a transfer mask is required for such a long substrate.

  As a direct exposure apparatus for drawing a pattern on a long substrate, for example, an exposure apparatus such as Patent Document 1 is known, but with such an exposure apparatus, a pattern can be exposed only on one side of a long substrate, It is necessary to remove the roll of the substrate after the exposure and re-install it on the input side to perform the exposure process once again, resulting in low productivity. On the other hand, in order to form an electronic circuit on both sides of a long substrate using a direct exposure apparatus, an exposure apparatus that forms a pattern by irradiating drawing light on both sides of the substrate as in Patent Document 2 is examined. Has been.

JP 2006-102991 A JP 2005-121959 A

  The exposure apparatus of Patent Document 2 has a problem in that an exposure stage having a size that covers the exposure range cannot be provided due to the structure in which drawing light is irradiated on both surfaces of the substrate. The exposure stage has a role of measuring the feed amount of the substrate with high accuracy and improving the flatness of the substrate, and it is difficult to draw a highly accurate pattern on the substrate without the exposure stage.

  Based on the above problems, the present invention provides a direct exposure apparatus that measures a substrate feed amount with respect to a long substrate with high accuracy, and further draws a pattern on both sides of the substrate while ensuring the flatness of the substrate. The purpose is to obtain.

  An exposure apparatus includes a light modulation element array, a first exposure unit that irradiates a first surface of a long substrate with pattern light modulated by the light modulation element array, and a part of the length of the long substrate in a planar shape. A first exposure stage held by the first exposure stage, a first relative movement means for moving the first exposure section and the first exposure stage relative to each other in the length direction of the long substrate, and a folding means for turning back the conveyance path of the long substrate. And a second exposure unit that irradiates the second surface of the long substrate with pattern light modulated by the light modulation element array, and a portion of the long substrate in the length direction is held in a flat shape. And a second relative movement means for relatively moving the second exposure unit and the second exposure stage in the length direction of the long substrate. By setting it as such an exposure apparatus, both surfaces of a elongate board | substrate can be exposed using an exposure stage. In addition, since the first exposure unit and the second exposure unit respectively irradiate pattern light downward, the pattern can be exposed on both surfaces of the long substrate under the same conditions.

  In addition, the first relative movement means and the second relative movement means move the first exposure stage and the second exposure stage synchronously in opposite directions along the length direction of the long substrate, respectively. The first exposure unit and the second exposure unit respectively modulate the pattern light applied to the long substrate according to the movement of the first exposure stage and the second exposure stage. Furthermore, a substrate supply means for feeding out a long substrate is provided, and the substrate supply means adjusts the speed at which the long substrate is fed in synchronization with the movement of the first exposure stage, and similarly takes up the substrate. Means for adjusting the speed at which the long substrate is taken up in synchronization with the movement of the second exposure stage. Accordingly, since the long substrate can be transported without providing the buffer portion of the substrate, it is possible to reduce a useless area where the pattern cannot be exposed on both surfaces of the long substrate such as near the roll end.

  Further, since the substrate supply means and the substrate winding means are provided on the same side of the exposure apparatus, the efficiency of the setup work such as roll change is improved.

  In addition, since the first relative moving means and the second relative moving means are provided at the same height, the height of the apparatus can be suppressed, and a compact exposure apparatus can be realized.

  According to the exposure apparatus of the present invention, it is possible to measure a substrate feed amount with respect to a long substrate with high accuracy and to draw a pattern on both surfaces of the substrate while ensuring the flatness of the substrate.

It is a front view which shows the whole structure of the exposure apparatus by this invention. It is a top view which shows the whole structure of the exposure apparatus by this invention. It is a front view which shows the structure of the exposure head of the direct exposure apparatus by this invention.

  FIG. 1 is a front view showing an overall configuration of an exposure apparatus 1 which is a roll-to-roll direct exposure apparatus according to the present invention. FIG. 2 is a plan view showing the overall configuration of the exposure apparatus 1. In FIG. 2, a part of the long substrate (work) W is seen through (broken line portion), and the portion hidden by the long substrate W is drawn.

  The exposure apparatus 1 exposes a pattern on the first surface of the long substrate W by exposing the pattern to the reel driving unit 10 that supplies and winds the long substrate W in order along the conveyance path of the long substrate W, and an electronic circuit. The first exposure processing unit 20 for forming the substrate, the folding unit 30 for folding the conveyance path, and the second exposure processing unit 40 for exposing the pattern to the second surface of the long substrate W to form an electronic circuit. Yes. Here, the first surface of the long substrate W means the upper surface side of the substrate unwound from the supply reel 11 of the reel driving unit 10, and the second surface means the lower surface side of the substrate unwound from the supply reel 11. Means.

  The long substrate W is a sheet-like substrate made of a copper-clad laminate coated with a photosensitive material such as a photoresist, and has a length of several tens to several hundreds of meters. The substrate of the FPC board is obtained by performing processes such as development, etching, and cutting after the exposure.

  The reel drive unit 10 includes a supply reel (substrate supply unit) 11, a take-up reel (substrate take-up unit) 12, and a guide roller 13, and rotates the supply reel 11 and the take-up reel 12 using a drive system (not shown). Drive. In addition, a sensor that detects the position of the end surface of the long substrate W, a mechanism that adjusts the tension applied to the long substrate W, and the like may be provided.

  Between the reel driving unit 10 and the first exposure processing unit 20, a guide roller 14 that changes the transport direction of the long substrate W by 90 °, a substrate braking roller 16 that brakes (holds) the substrate, and an edge that detects the substrate end surface A sensor 21 and a correction roller 15 that changes the conveyance direction of the long substrate W by 90 ° and adjusts the position of the substrate end surface according to the output of the edge sensor 21 are provided.

  The first exposure processing unit 20 includes an exposure stage 24 (first exposure stage), a pair of alignment cameras 22 (see FIG. 2), and a first exposure unit (exposure unit) 23. A pattern is formed on the first surface of the long substrate. To expose. Here, the moving direction (transport direction) of the long substrate W in the exposure processing unit 20 is the X direction, the direction orthogonal to the long substrate W (thickness direction) is the Z direction, and the direction orthogonal to the X direction and the Z direction is. It is defined as the Y direction.

  The first exposure unit 23 includes a plurality of exposure heads (not shown), and is regularly arranged at a position vertically away from the long substrate W by a predetermined distance.

  FIG. 3 is a schematic diagram showing the configuration of one exposure head. The light emitted from the light source (such as a mercury lamp) OP1 becomes parallel light via the illumination optical system OP2 and the folding mirror OP3 and enters the light modulation element array OP4. The light modulation element array OP4 is, for example, a DMD (Digital Micro-mirror Device) in which a plurality of micromirrors are two-dimensionally arranged. The light (UV) modulated by the light modulation element array OP4 is imaged on the long substrate by the imaging optical system OP5. In addition, the exposure head includes a focusing optical system OP6 that adjusts the imaging position along the optical axis direction.

  A technique of performing multiple exposure of a pattern using DMD is a well-known technique disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-084444 and widely used. Further, a technique for drawing one pattern using a plurality of heads is a well-known technique disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-195512 and widely used.

  The exposure stage 24 sucks (for example, vacuum sucks) the back surface of the long substrate W and holds it in a flat shape, and is freely movable in the X direction and the Z direction. That is, a stage moving unit (first relative moving unit) 25 that is movably supported by a guide rail extending in the X direction is provided on the gantry BF, and an elevating unit 26 that moves the exposure stage 24 up and down is supported. The stage moving unit 25 is provided with means (not shown) for measuring the position of the stage moving unit 25 such as a linear scale or a laser displacement meter. The moving amount of the exposure stage 24 (that is, the feed amount of the long substrate W). ) Can be measured accurately.

  The exposure stage 24 moves up and down between the upper end position contacting the back surface of the long substrate W and the lower end position spaced apart from the back surface of the long substrate W by the lifting unit 26. The stage moving unit 25 can move forward and backward (downstream and upstream) in the X direction. The stage moving unit 25 constitutes a relative moving unit that relatively moves the exposure stage 24 and the exposure unit 23 in the length direction of the long substrate W. The range (area) in which the exposure stage 24 can hold the long substrate W at a time is, for example, 620 (X) × 520 (Y) mm.

  The pair of alignment cameras 22 is installed on the upstream side of the exposure unit 23 and images an alignment mark (not shown) provided on the long substrate W. An image captured by each alignment camera 22 is subjected to image processing by an image processing unit (not shown) and used for calculating a correction amount when aligning the long substrate W and the exposure unit 23.

  The folding portion (folding means) 30 is provided with guide rollers 31 and 33 and a substrate braking roller 32 for braking the substrate. Since the guide rollers 31 and 33 bend the long substrate W by 90 °, the conveyance direction of the long substrate W is reversed by 180 ° before and after the folded portion 30. Accordingly, the first surface of the long substrate W is on the lower surface side and the second surface is on the upper surface side after the folded portion 30.

  Between the turn-back unit 30 and the exposure processing unit 40, the long substrate W is conveyed through a passage provided in the gantry (base unit) BF. Further, between the folding unit 30 and the exposure processing unit 40, a guide roller 16, a guide roller 17 that changes the conveyance direction of the long substrate W by 90 ° and brakes the substrate, and an edge sensor 41 that detects the substrate end surface. And a correction roller 15 that changes the conveyance direction of the long substrate W by 90 ° and adjusts the position of the substrate end face according to the output of the edge sensor 21.

  The second exposure processing unit 40 includes an exposure stage 44 (second exposure stage), a pair of alignment cameras 42 (see FIG. 2), and a second exposure unit (exposure unit) 43, and a pattern is formed on the second surface of the long substrate. To expose.

  The alignment camera 42, the second exposure unit 43, the exposure stage 44, the stage moving unit 45, and the elevating unit 46 are respectively the alignment camera 22, the first exposure unit 23, the exposure stage 24, and the stage moving unit 25 of the first exposure processing unit 20. It has the same function as the elevating unit 26. On the other hand, the first exposure processing unit 20 and the second exposure processing unit 40 are different in the transport direction of the long substrate.

  That is, the 1st exposure process part 20 and the 2nd exposure process part 40 are symmetrical arrangement | positioning so that it may oppose in the X direction, and operate | move so that it may conflict in the X direction. For example, referring to FIG. 1, when the exposure stage 24 of the first exposure processing unit 20 performs scanning exposure on the first surface of the long substrate W while moving in the left direction, the exposure of the second exposure processing unit 40 is performed. The stage 44 performs scanning exposure on the second surface of the long substrate W while moving in the right direction.

  In the exposure apparatus of the present invention, the exposure operation is performed in accordance with the transport speed of the long substrate W in each part. For example, the supply reel 11 unwinds the substrate in synchronization with the movement of the exposure stage 24. This is realized by constantly adjusting the reel rotation speed in accordance with the remaining amount of the long substrate W on the supply reel 11. The relationship between the movement of the exposure stage 44 and the unwinding of the take-up reel 12 is the same. Further, the exposure stage 24 and the exposure stage 44 operate similarly in synchronization.

  In this way, by adjusting the transport speed and each part transporting the long substrate W in synchronism, an area that occurs near the roll end of the long substrate W and cannot be subjected to pattern exposure on both sides of the substrate (for setup purposes) Can be shortened.

  In the exposure apparatus of the present invention, the stage moving unit 25 and the stage moving unit 45 are installed on the same height base provided on the same frame BF. By adopting such a configuration, the configuration of the exposure apparatus becomes simple and the exposure apparatus becomes compact.

  Further, in the exposure apparatus of the present invention, the supply reel 11 and the take-up reel 12 are arranged on the same side of the exposure apparatus (the right end part of the exposure apparatus in FIG. 1) due to the structure in which the turn-back portion 30 is provided. Such an arrangement facilitates reel replacement and improves productivity.

  Next, the operation of the exposure apparatus of the present invention will be described. The operation of the exposure apparatus 1 alternately performs a transport step for transporting the long substrate W and a preparation step for stopping transport of the long substrate W and preparing for the next transport step.

  In the transport step, the reel driving unit controls the rotation speeds of the supply reel 11 and the take-up reel 12, and feeds and winds the long substrate W at a predetermined speed. Further, the first exposure unit 23 and the second exposure unit 43 are used by using the drawing data corrected in accordance with the alignment result in the preparation step while the exposure stages 24 and 44 move in the X direction while adsorbing the long substrate W. Exposes the pattern on the first and second surfaces of the long substrate. Note that the substrate braking rollers 16 and 32 release the braking during the transport step.

  In the preparation step, the reel driving unit stops the supply reel 11 and the take-up reel 12 and puts the substrate braking rollers 16 and 32 into a braking state. The substrate suction of the exposure stages 24 and 44 is released, and the elevating part is lowered to separate the exposure stage and the long substrate W from each other. Next, the exposure stages 24 and 44 are returned to the scanning start position, and the elevating unit is raised. The substrate braking rollers 16 and 32 release the braking, and the exposure stages 24 and 44 suck the long substrate W. The alignment cameras 22 and 42 image the alignment mark while driving the exposure stage and the reel driving unit, and perform a drawing data position correction process. Thereafter, the positions of the exposure stages 24 and 44 are adjusted so that the long substrate W comes to the pattern exposure start position.

  By repeating the above two steps, a pattern can be formed on both sides of the long substrate W.

  Although the above embodiment has been described with reference to FIG. 1, the present invention can be applied even when the substrate transport direction is different from FIG. For example, the first exposure processing unit 20 and the second exposure processing unit 40 may be interchanged to reverse the transport direction of the long substrate W. In that case, the roles of the supply reel 11 and the take-up reel 12 may be switched. Alternatively, the mirror image relationship of FIG. 1 may be adopted so that the reel driving unit 10 comes to the left end of the exposure apparatus.

  In the above embodiment, the first exposure processing unit and the second exposure processing unit are described as having the same height. However, in order to reduce the length of the exposure apparatus in the X direction, the exposure processing units partially overlap in the Z direction. You may arrange as follows.

  Moreover, you may provide board | substrate buffers, such as a dancer roller, in each part of the conveyance path | route of a long board | substrate as needed. In this case, the area where the double-sided exposure cannot be performed near the roll end of the long substrate becomes large, but the conditions regarding the synchronization of each part can be relaxed, and the cause of the transport error can be reduced.

  As described above, according to the exposure apparatus of the present invention, by using an exposure stage for a long substrate, the substrate feed amount is measured with high accuracy and the flatness of the substrate is ensured. An exposure apparatus that draws a pattern on both surfaces of the substrate in a state can be obtained.

DESCRIPTION OF SYMBOLS 1 Exposure apparatus 10 Reel drive part 11 Supply reel 12 Take-up reel 20 1st exposure process part 22 Alignment camera 23 1st exposure unit 24 Exposure stage 30 Folding part 40 2nd exposure process part 42 Alignment camera 43 2nd exposure unit 44 Exposure Stage BF Base W Long substrate

Claims (7)

A first exposure unit including a light modulation element array, and irradiating a first surface of a long substrate with pattern light modulated by the light modulation element array;
A first exposure stage for holding a part of the length of the long substrate in a planar shape;
First relative movement means for relatively moving the first exposure unit and the first exposure stage in the length direction of the long substrate;
A folding means for folding the transport path of the long substrate;
A second exposure unit that includes a light modulation element array, and irradiates the second surface of the long substrate with pattern light modulated by the light modulation element array;
A second exposure stage for holding a part of the long substrate in the length direction in a planar shape;
Second relative movement means for relatively moving the second exposure unit and the second exposure stage in the length direction of the long substrate;
An exposure apparatus comprising:   The exposure apparatus according to claim 1, wherein the first exposure unit and the second exposure unit irradiate the pattern light downward. The first relative movement unit and the second relative movement unit move the first exposure stage and the second exposure stage in synchronization with each other in opposite directions along the length direction of the long substrate. As well as
The said 1st exposure part and the said 2nd exposure part respectively modulate the pattern light irradiated to the said elongate board | substrate according to the movement of a said 1st exposure stage and a said 2nd exposure stage. The exposure apparatus according to claim 1 or 2. Comprising substrate supply means for feeding out the long substrate;
4. The exposure apparatus according to claim 1, wherein the substrate supply unit adjusts a speed at which the long substrate is sent out in synchronization with the movement of the first exposure stage. A substrate winding means for winding the long substrate;
The exposure apparatus according to claim 4, wherein the substrate winding unit adjusts a speed of winding the long substrate in synchronization with the movement of the second exposure stage.   6. The exposure apparatus according to claim 5, wherein the substrate supply unit and the substrate winding unit are provided on the same side of the exposure apparatus.   The exposure apparatus according to claim 1, wherein the first relative movement unit and the second relative movement unit are provided on a base portion having the same height.

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